Great Retreat

The Great Retreat occurred from 24 August to 5 September 1914 when the French and British forces on the Belgian frontier withdrew from Mons in Belgium to the River Marne in northern France as German forces overwhelmed Belgium and northern France. The French government fled to Bordeaux, fearing that Paris would fall to the Germans, but the Entente forces rallied at the Marne, where they halted the German advance in the First Battle of the Marne, turning the tide of the war.

Background
In August 1914, the German Schlieffen Plan, intended to defeat France in six weeks, appeared to be working. But in reality, the German offensive was going awry. The basis of the Schlieffen Plan was the concentration of German forces on their right wing to sweep through Belgium and northern France. These forces became fatally weakened. Troops had to be detached to besiege the Belgians at Antwerp and the French forces at Maubeuge. The German offensive from Lorraine was reinforced at the expense of the armies on the right. On 26 August, two German corps were sent to the Eastern Front to face the Russian threat to East Prussia.

In spite of their massive losses, the French maintained their coherence and fighting spirit. The British confirmed their commitment to the war by sending another infantry division to France on 19 August.

Retreat
On 25 August, Joseph Joffre issued his General Instruction No. 2. This envisioned a withdrawal of the French and British armies to a defensible line - initially set at the Somme, but later revised to the Marne - where the German advance would be halted. A new French 6th Army would be created and moved by rail north of Paris to help repel the German armies flooding into France from Belgium. This strategic vision seemed more fantasy when set against the reality faced by French and British troops on the ground.

The battered British Expeditionary Force (BEF) and French 5th Army were marching up to 12 miles a day in burning summer heat with the German First and Second Armies at their heels. Occasionally, British and French troops fought rearguard actions, including a successful French counterattack at St. Quentin. Mostly they marched, often short of food and drink, their feet blistered, and snatching sleep by the roadside. In Paris, there was panic as the Germans approached. The French government fled to Bordeaux while General Joseph Gallieni defended the capital. Meanwhile, the BEF commander, Field Marshal Sir John French, had lost all confidence in his allies. Determined to save his army from destruction, he planned to withdraw his army. The British war minister, Lord Herbert Kitchener, made a lightning visit to Paris and told him to stay in line.

The line holds
By early September, Joffre's plans were taking shape. The French continued to hold against German attacks in front of Nancy and Verdun. The French Third and Fourth Armies lost more ground, including the city of Reims on 5 September, but a defensive line was emerging, with a new Ninth Army under the command of General Ferdinand Foch inserted between the Fourth and Fifth Armies.

Meanwhile, the strains imposed on Allied troops by the Great Retreat were mirrored on the German side. Soldiers on the German right wing had been marching for a month since crossing the Belgian border. Dependent on horse-drawn transportation, their supplies failed to keep up, leaving troops hungry and thirsty. The German First and Second Armies, advancing in parallel, had difficulty keeping in touch with each other and with Moltke's staff headquarters in Luxembourg. Although Moltke had planned for the First Army to march west of Paris, its commander, General Alexander von Kluck, chose to turn east of the capital, heading for the Marne River. This was a disastrous decision, for it left the right flank of Kluck's army exposed to potential attack by both the Paris garrison and Joffre's newly formed Sixth Army.

Time to attack
In the first days of September, the Great Retreat was still under way. The BEF and French Fifth Army withdrew across the Marne River on 2 September with Kluck a day behind them, his rapid advance opening up a gap between his army and General Karl von Bulow's Second Army. Joffre was still hesitating over the optimum moment to launch his counterblow, but Gallieni, with not only the Paris troops but also the Sixth Army under his overall command, forced Joffre's hand. Informed from various sources, including reconnaissance, of Kluck's exposed flank, on 4 September Gallieni sent out orders to prepare to attack. Accepting Gallieni's initiative, on the following day Joffre informed his armies, "The time for retreat has ended."

Aftermath
As the Great Retreat came to a halt, Joffre launched the First Battle of the Marne. This counteroffensive was a turning point of the war. Pressure for a swift counterattack came from General Gallieni in Paris and General Louis Franchet d'Esperey, the new commander of the French Fifth Army. They obtained Joffre's agreement for the offensive on the Marne to start on 6 September. Field Marshal Sir John French agreed to stop retreating only after Joffre appealed to "the honor of England" on 5 September.

On the German side, Kluck's First Army advanced across the Marne on 5 September, despite orders from Moltke to go on the defensive. Kluck did not pull back until the following day. The Germans managed the transition from headlong attack to a fighting withdrawal skilfully. They eventually stabilized a defensive position at the Aisne River.